Glaucoma is a group of eye diseases that damage the optic nerve and can lead to vision loss. It usually has no symptoms at first, and the National Eye Institute (NEI) says half of people with glaucoma don't know they have it. NEI lists people over 60 as higher risk and says anyone at higher risk needs a comprehensive dilated eye exam every 1 to 2 years. There is no cure, but early treatment can often stop the damage and protect your vision.
Many eye problems make themselves known with blur, glare or wavy lines. Glaucoma usually does not. NEI says many people with the most common type don't have any symptoms until they start to lose their vision, and treatment cannot undo damage that is already done.
This guide explains what glaucoma is, who is at higher risk after 60, the one type that is a medical emergency, how it is found, and how it is treated. It draws on the NEI glaucoma page and the CDC's page about glaucoma. Where the two word things differently, we quote each one separately.
What glaucoma is
NEI describes it this way: "Glaucoma is a group of eye diseases that can cause vision loss and blindness by damaging a nerve in the back of your eye called the optic nerve."
Eye pressure is part of the story. NEI explains that many people with glaucoma have high eye pressure, and that treatments that lower eye pressure help slow the disease. But pressure is not the whole picture. NEI notes that some people with high eye pressure don't get glaucoma, and that there is a type of glaucoma that happens in people with normal eye pressure.
NEI is also clear about what treatment can and cannot do: "There's no cure for glaucoma, but early treatment can often stop the damage and protect your vision." Treatment won't undo damage that has already happened.
Why you can have glaucoma and not know it
NEI says: "At first, glaucoma doesn't usually have any symptoms. That's why half of people with glaucoma don't even know they have it." The CDC gives the same figure: "Half of people with glaucoma don't know they have it."
When vision loss does start, it usually affects side vision first. NEI says the loss usually begins with your side (peripheral) vision, especially the part closest to your nose. The CDC describes peripheral vision as "what you see to the side while looking forward". NEI adds that "Without treatment, glaucoma can eventually cause blindness."
This is different from age-related macular degeneration (AMD), which affects central vision. If you are comparing conditions, our articles on cataracts vs macular degeneration and the symptoms of macular degeneration cover those changes.
Types of glaucoma
NEI's page on types of glaucoma describes the main forms:
- Open-angle glaucoma. This is the most common type in the U.S. NEI says "9 in 10 people with glaucoma have the open-angle type," and that many people don't have any symptoms until they start to lose their vision. NEI adds that people with high blood pressure or diabetes are at higher risk for this type.
- Normal-tension glaucoma. NEI calls this "a type of open-angle glaucoma that happens in people with normal eye pressure."
- Angle-closure glaucoma. NEI says this type, also called narrow-angle or acute glaucoma, "is a medical emergency." If it is not treated, it can cause blindness in just a few days. NEI notes there is also a slow, chronic form that might not have any symptoms.
- Congenital glaucoma. NEI lists this as a less common type.
Emergency signs of angle-closure glaucoma. NEI says angle-closure glaucoma can cause these sudden symptoms:
- Intense eye pain
- Upset stomach (nausea)
- Red eye
- Blurry vision
If you have any of these symptoms, go to your doctor or an emergency room now. Do not wait to see whether they pass.
Who is at higher risk after 60
NEI and the CDC both list age over 60 as a risk, but their lists are worded differently. Here is each one as the agency gives it.
| NEI (Glaucoma page, updated August 2026) | CDC (About Glaucoma, reviewed May 2024) |
|---|---|
| People over age 60, especially if Hispanic/Latino | All people over age 60 |
| African American and over age 40 | Black people over age 40 |
| A family history of glaucoma | People with a family history of glaucoma |
| (NEI's Types of Glaucoma page adds that high blood pressure or diabetes raises the risk of open-angle glaucoma) | People who have diabetes |
The CDC also gives these figures: "Black people are 6 to 8 times more likely to get glaucoma than White people. People with diabetes are 2 times more likely to get glaucoma than people without diabetes." It says "About 3 million Americans have glaucoma, and it's the second leading cause of blindness worldwide." The CDC page does not give a data year or a study source for these numbers.
How glaucoma is found
NEI puts it plainly: "The only way to find out if you have glaucoma is to get a comprehensive dilated eye exam." NEI adds that the exam includes a visual field test to check your side vision. NEI's glaucoma page summarizes diagnosis as a dilated eye exam with visual field testing.
NEI's dilated eye exam page lists the parts of a full exam:
- A visual acuity test (how clearly you see)
- A visual field test, to check your peripheral (side) vision
- An eye muscle function test
- A pupil response test
- Tonometry, to measure the pressure in your eyes
- Dilation, using eye drops to widen your pupils
As that page points out, "Since many eye diseases have no symptoms or warning signs, you could have a problem and not know it."
How often? NEI says: "If you're at higher risk, you need to get a comprehensive dilated eye exam every 1 to 2 years." Our guide to eye health after 50 brings together exam schedules for other conditions too. A home Amsler grid, which our Amsler grid guide explains, is a check for people with AMD and is not a way to find glaucoma.
About cost: the CDC says "Medicare covers a glaucoma test once a year for people in high-risk groups." Ask your eye doctor's office or Medicare whether you qualify.
How glaucoma is treated
NEI lists three main approaches:
- Eye drops. "Prescription eye drops are the most common treatment," according to NEI.
- Laser treatment. Done in the eye doctor's office, it helps fluid drain out of the eye.
- Surgery. An option if medicines and laser treatment don't work.
The CDC describes treatment as "eye drops, oral medicine, or surgery (or a combination of treatments) to reduce pressure in the eye," and says "These treatments can prevent or delay permanent vision loss."
NEI is clear about the limits: "Treatment won't undo any damage to your vision, but it can stop it from getting worse." That is the main reason finding glaucoma early matters.
Living with glaucoma
If you have been diagnosed, NEI suggests a few habits:
- Take your prescribed medicine every day.
- Tell your eye doctor about any side effects.
- Keep up with regular check-ups.
- Encourage family members to get checked, since glaucoma can run in families.
Can glaucoma be prevented?
NEI says: "There's no way to prevent glaucoma." It follows that statement by explaining that this is why eye exams are so important. Regular dilated exams, especially if you are in a higher-risk group, are how glaucoma is found early enough for treatment to protect your sight.
Frequently asked questions
My vision seems fine. Do I still need a glaucoma check?
Yes, if you are in a higher-risk group. NEI says glaucoma usually has no symptoms at first and that half of people with it don't know they have it. The only way to find out is a comprehensive dilated eye exam.
If my eye pressure is normal, can I still have glaucoma?
Yes. NEI says there is a type of glaucoma that happens in people with normal eye pressure. NEI's exam includes a visual field test to check side vision, not only a pressure check.
Which glaucoma symptoms mean I should get help right away?
Sudden intense eye pain, upset stomach (nausea), a red eye or blurry vision can be signs of angle-closure glaucoma. NEI says to go to your doctor or an emergency room now.
Related reading
- Eye Health After 50
- Cataracts vs Macular Degeneration
- How to Use an Amsler Grid
- Smoking and Eye Health
- Browse the Eye Health Library
References
- National Eye Institute. Glaucoma (updated August 19, 2026). nei.nih.gov
- National Eye Institute. Types of glaucoma (updated December 5, 2024). nei.nih.gov
- National Eye Institute. Get a dilated eye exam (updated November 26, 2025). nei.nih.gov
- Centers for Disease Control and Prevention. About glaucoma (published May 15, 2024; updated November 17, 2023; reviewed May 15, 2024). cdc.gov
This article is for general education and is not medical advice. Talk with your eye doctor before starting any supplement, especially if you smoke, take other medicines, or have a health condition. These statements have not been evaluated by the Food and Drug Administration. TruVista products are not intended to diagnose, treat, cure, or prevent any disease.
